prebiotic

In the poultry industry, additives are used to stimulate growth, improve production performance, and improve the health of the flock. On the other hand, reducing the quality of food items and their protein level, as well as the high level of anti-nutritional substances, disturbs the balance of the microbial ecosystem of the digestive system of birds and health and ultimately reduces their performance. The health and nutritional status of poultry is largely dependent on the microbial flora of the digestive system, which directly and indirectly affects the morphology of the digestive system, nutrition, and immune system. The microbial flora of the intestine is relatively unstable and is easily affected by various nutritional factors. Therefore, this research aimed to investigate the effect of the simultaneous use of organic acids and prebiotics in diets containing low-quality soybean meal on the performance of laying hens.

This experiment was conducted using a completely randomized design in a 2 x 2 factorial arrangement using two levels of mixed organic acids and prebiotics and two types of soybean meal in the diet of laying hens. Chickens were distributed among pens based on weight and production rates for 2 weeks. Then, 192 laying hens of the LSL strain at the end of 73 weeks of age, after weighing and entering the wing number, were placed in 48 experimental cages, including four treatments with 12 replications, and fed for 12 weeks. Experimental treatments were treatment I (without the combination of organic acids and probiotics and containing 42% protein soy), treatment II (without the combination of organic acids and probiotics and containing 38% protein soy), treatment III (the combination of organic acids and probiotics and containing 42% protein soy), and treatment IV (a combination of organic acids and probiotics with 38% protein soy). To add the combination of organic acids and prebiotics, organic acid was used at a level of 1 kg per ton. The composition of the product included 30% propionic acid, 10% butyric acid, and 15% acetate plus 20% prebiotic with the origin of the Saccharomyces cerevisiae yeast cell wall. Performance traits, including production percentage and egg weight, egg mass weight, and feed conversion ratio (FCR) were measured at the end of the experiment (age 85 weeks) when all the birds were killed using the cervical vertebrae displacement method. The abdominal fat response of the immune system, histomorphology of the small intestine, and microbial population of the cecum were the investigated parameters.

Except for the first week of the experiment, the addition of the combination of organic acids and probiotics and the use of high-quality soybean meal in the diet significantly increased the egg-laying percentage during the rest of the experiment (p < 0.01). In the first 4 weeks of the experiment (weeks 75-78), the percentage of egg production was under the significant influence of the interaction effects of the experimental factors. The treatment with organic acids plus prebiotics and high-quality soybean meal (treatment 3) presented the highest egg production rate (p< 0.05). From the second week to the end of the experiment, the consumption of diets containing the combination of organic acids and probiotics and high-quality soybean meal significantly increased the weight of the produced eggs (p< 0.05). The interaction effects of experimental treatments during the experimental period did not show a constant trend in the weight of produced eggs (p≥ 0.05). Adding the combination of organic acids and probiotics to the diet elevated egg mass in the entire experimental period, the difference of which was significant (p< 0.05). The use of soybean meal with low-protein soybean meal in the diet during the experimental period decreased the weight of the egg mass compared to the group consuming the diet containing high-quality soybean meal (p< 0.05). Adding the combination of organic acids and probiotics and the use of high-quality soybean meal in the diet of the studied laying hens improved the FCR during the test period (p< 0.05). The FCR in the first 5 weeks of the experiment was under the interaction effects of the experimental factors (p< 0.05). Abdominal fat at the beginning (age 73 weeks) and the end of the experiment (age 85 weeks) did not show significant differences between different treatments (p≥ 0.05). Cellular immune response to DNCB injection significantly increased using the organic acids and prebiotic mixture and decreased with the presence of low-protein soybean meal in the diet (p < 0.05). The microbial population of the cecum changed significantly under the influence of the interaction effects of the mixture of organic acids and prebiotics and the quality of the feed soup (p < 0.05). The use of a mixture of organic acids and prebiotics caused a significant increase in the height of the duodenal villi (p< 0.05). The presence of low-protein soybean meal in the diet significantly elevated the depth of crypts (p< 0.05). The ratio of villus height to crypt depth changed under the significant influence of the interaction effects of the experimental factors. The highest ratio was recorded in the treatment with a mixture of organic acids and prebiotics and high-quality soybeans in the diet while the lowest ratio was measured in the treatment without a mixture of organic acids and prebiotics and low-protein soybeans in the diet (p< 0.05). The width of the duodenal villi did not change under the influence of experimental factors, with no significant differences (p≥ 0.05).

In general, the results showed that using a combination of organic acids and probiotics in the diet of laying hens improved their productive performance and the health of their digestive system, as well as the performance of chickens fed with low-protein soybean meal.

Effect of different sources of probiotic and prebiotic on growth performance, carcass characteristics, intestinal microflora, and blood metabolites using 720 Ross 308 commercial male broiler chickens in a 3×3 factorial experiment with three levels of probiotic (without probiotic, probiotic type I and type 2) and three levels of prebiotic (without prebiotic, prebiotic type 1 and type II), in a completely randomized design with nine experimental groups (four replications and 20 birds were studied in each replication. Birds that were fed with diets containing type 2 probiotics had a lower conversion factor (P<0.05). Diets containing prebiotic type 1 as well as diets containing probiotic type II and diets containing probiotic type II and two prebiotics under test reduced serum cholesterol and LDL concentrations (P < 0.05). The effect of the experimental treatments on carcass fat was not significant, but the birds fed diets containing prebiotic type 1 had less abdominal fat (P<0.05). At 21 days old, the population of E. coli in the ileum and ceca of birds that received probiotics, prebiotics, and their combinations decreased (P < 0.05). At 38 days of age, feeding the birds with probiotics and prebiotics and a combination of them reduced the population of E. coli in the ceca and increased lactobacillus in the ileum (P < 0.05). The results of this experiment showed that probiotics or prebiotics assayed in this study have positive effects on the increase of beneficial intestinal bacteria (Acid lactic bacteria), blood biochemical traits, and FCR in broiler chickens.

Gastrointestinal tract infections and subsequent diarrhea are the main reason of mortality of newborn calves. Diarrhea is the most common disease that occurs in cattle farms and causes death and serious economic losses to the livestock industry. Due to negative effects of antibiotics, including Bacterial resistance to antibiotics, many countries in the world have banned the use of these antibiotics in the animal industry since 1996. The use of probiotics is mostly seen as an alternative to antibiotics in animals, and many scientific works show the beneficial effects of supplements with probiotic strains in the diets of different farm animals. Probiotics have been shown to have positive effects on the whole body, including weight gain and immune function, and reducing the presence of pathogens. This study aimed to evaluate the probiotics Bacillus coagulans and Bacillus subtilis and their effect on the growth performance, health, and prevalence of diarrhea in suckling Holstein calves. . . . . . .

The present study was conducted in the form of a completely randomized design with 32 replications in two treatments. Calves were monitored for 28 days. Body weight was measured every week, and dry matter intake and health status were checked and measured every day. Blood samples were taken from the calves on the first, seventh, 14th, 21st, and 28th days, and the blood was kept at 4°C until reaching the laboratory, and then blood parameters were measured. fecal samples were taken for microbial culture on the 7th, 14th, and 28th days and were cultured in the laboratory.

The results showed that probiotic supplementation does not affect weight, daily weight gain, skeletal growth, Feed Efficiency, and hematological parameters. However, feed intake and the number of Lactobacillus in feces increased significantly (P < 0.05). Additionally, probiotic supplementation reduced fecal score, diarrhea duration, and body temperature significantly (P<0.05).

Probiotic oral supplement improved the symptoms of diarrhea and the negative effects of diarrhea, and it also improved the performance of feed consumption and increased the beneficial bacteria of the gastrointestinal tract system in suckling calves. By preventing diarrhea, probiotic supplements can reduce the losses caused by calves dying and, as a result, make dairy farms more profitable.

High stocking density is known as a source of chronic stress, which has an adverse effect on the performance of laying hens. So, the aim of this study was to investigate the effect of different levels of autolyzed yeast on performance and egg quality traits of laying hens reared under high stocking density. This experiment was done using 2 levels of density (2 and 4 birds per cage with dimensions of 38×38 cm) and 4 levels of autolyzed yeast (0, 0.2, 0.4 and 0.6 percentage) with 192 laying hens Hy-line W-80 (35 weeks old) in a completely randomized design with factorial arrangement of 4×2 with 8 replicates. The results of the experiment showed that high stock density decreased the viability and reduced the feather score of birds, but autolyzed yeast increased the viability of birds in high stock density (P≤0.05). Dietary supplementation of autolyzed yeast was not affected feed intake (P≥0.05), but increased egg production and decreased feed conversion ratio (P≤0.05). The increase in egg weight showed a tendency to be significant (P=0.07). Dietary supplementation of autolyzed yeast decreased pH of excreta in laying hens (P≤0.05). Also, autolyzed yeast increased the primary and secondary antibody titer against sheep red blood cell at the 43 and 44 weeks old (P≤0.05). The results of this experiment showed that the supplementation of autolyzed yeast to the diet improved performance and the humoral immune system of laying hens reared at high stock density.

The inclusion of prebiotics in layer hen diets can act as a growth-promoting antibiotic replacer and have beneficial effects on egg production and egg quality. This study aimed to investigate the effects of liquid prebiotic on the post-molt laying performance, egg quality at different storage temperatures and times, immune system function, and blood biochemical parameters of laying hens.

A total of 144 White Leghorn Hy-Line W-36 laying hens at 83 wk of age were randomly assigned to 6 dietary treatments, 4 replicates, and 6 birds per each for 6 weeks in a complete randomized design experiment. Experimental diets were: 1- A corn-soybean meal-based diet without adding liquid prebiotic as a control, 2 to 5- Supplementing basal diets with 0.5, 1, 1.5, 2 ml of liquid prebiotic per Kg of diet, 6- basal diet with adding 500 mg of oxytetracycline as an antibiotic per kg of diet. Laying performance including egg production, egg weight, egg mass were recorded daily, and feed intake and feed conversion ratio were calculated weekly. In order to evaluate the egg quality traits at various storage temperatures (refrigerator temperature (4ºC) and room temperature (25ºC) and storage periods (0, 7, 14 days), two eggs were randomly selected from each replicate in the 2th, 4th and 6th weeks of the experiment and the egg quality traits were measured. To evaluate the effects of liquid prebiotic supplementation on humoral immunity, antibody production against sheep red blood cells (SRBC) was used. The data were subjected to statistical analysis using a completely randomized design by SAS 9.1 software (SAS, 2004). The egg quality traits data were subjected to analysis of variance in a completely randomized design as a 6×3×2 factorial arrangements (6 levels of liquid prebiotic and antibiotic supplementations, 2 different storage temperatures and 3 storage periods).

The results showed that by increasing the prebiotic supplementation, the daily egg production (p=0.0057) and egg mass (p=0.0013) were linearly increased, and feed conversion ratio (p=0.0016) were linearly decreased. The effect of adding liquid prebiotic on egg quality traits including egg shape index, shell percentage, and shell thickness was not significant (p>0.05), but the effect of storage period on egg shape index and the effect of storage temperature on shell thickness and egg shape index was significant (p<0.05). Supplementation of diets with liquid prebiotic was significantly influenced the cholesterol, glucose, calcium, and aspartate aminotransferase (AST) concentrations of laying hens (p<0.05). The total antibody titer (IgT) against SRBC was increased by increasing supplemental prebiotic.

In conclusion, supplementation of 2 ml/kg liquid prebiotic in the diet of layer hens at post-molt period can act as an alternative to antibiotic growth promoters, thus the laying performance was enhanced, and by augmentation of production the specific immunoglobulins, the immune status was improved.

Spirulina platensis (SP) is a filamentous blue-green microalgae (cyanobacteria) generally regarded as prebiotic and source of high quality protein, minerals, essential fatty acids, essential amino acids, pigments and phenolic acids. Many studies have shown that Spirulina has antioxidant, immunomodulatory, anti-inflammatory, antiviral, and antimicrobial activity in various experimental animals. Several studies have demonstrated the growth-promoting effects of spirulina platensis on broiler chickens. Jamil et al., (2015) showed that feeding 0.2, 0.4, or 0.8 percent spirulina increased weight gain and linearly decreased feed conversion ratio (FCR) of broiler chickens. Similar results were reported by Shanmugapriya et al., (2015). They reported that feeding 1% of spirulina platensis to broiler chicks caused to improve growth performance. As well as growth performances, treatment with S. platensis was reported to increase the carcass percentage and ready-to-cook yields of broiler chicks in the studies of Raju et al. (2004), Kaoud (2012) and Holman & Malau-Aduli (2013). The cecum plays an important role in preventing colonization of pathogens and detoxifying harmful substances (Jorgensen et al., 1996), therefore may play an important role in improving nutrients absorption and better performance. A previous study in broiler chickens also concluded that intestinal microbial-including cecum is highly associated with the production performance of broiler chickens (Jeong and Kim, 2014). Park et al., (2018) indicated that broiler chickens fed a Spirulina supplemented diet led to higher cecal Lactobacillus concentration, but had no effect on the number of coliform bacteria. Some other studies suggest that microalgae have potential antibacterial, antiviral, and antifungal activities. de Mule et al., (1996) observed that methanolic and aqueous extracts of Spirulina inhibited the growth of Candida albicans whereas Lactococcus lactis was promoted by the extract, with growth increasing from 7.5 to 14.7%.

Three hundred one-day- old male Ross 308 broiler chicks were assigned to 5 dietary treatments with 6 replicates and 10 birds each in a completely randomized design. Dried Spirulina Platensis (SP) powder provided from Pars Jolbak Co. in Shiraz, Iran and after chemical analysis was used in diets. All experimental diets were corn soybean based and formulated to reach ROSS 308 broiler chicken requirements. Dietary treatments were 0 (control), 0.25, 0.5,0.75 and 1 % Spirulina Platensis (SP). All diets were isocaloric and isonitrogenous and were fed to birds during 6 weeks. The average daily feed intake (FI) and weight gain (WG) were measured for each group and feed conversion ratio was calculated. Daily mortality was weighed, recorded and used to correct the feed conversion ratio. Daily FI was determined from the difference between supplied and residual feed in each pen and was adjusted for mortality. At the end of the experiment, two birds per each replicate (similar to cage average weight) were selected. The birds were killed by cervical dislocation. Breast, thigh, pancreas, abdominal fat and liver were removed, weighed and expressed as a percentage of live weight at 42 d of age. At the end of experiment, cecal samples collected from each bird. One gram of cecal sample from viable counts of bacteria in the cecal samples were conducted by plating serial 10-fold dilutions onto Lactobacilli MRS agar plates and MacConkey agar plates to isolate Lactobacillus spp. and coliform bacteria, respectively. The lactobacilli agar plates were then incubated for 24-72 h at 37◦C under anaerobic conditions. After the incubation periods, colonies of the respective bacteria were counted and expressed as the logarithm of colony-forming units per gram (log10 CFU/g). All data analyzed by ANOVA using the GLM procedure described by the SAS Institute (2009). Tukey test was used to determine the significant differences between the treatment means.

The results showed that feed intake of birds was not influenced by SP supplementation during the whole period, but weight gain of birds fed diets containing 1 % SP, was increased (P<0.05) and feed conversion ratio was decreased significantly (P<0.05) as compared as control birds. Similar to our results, Park et al., (2018) showed that up to 1% SP in broiler diets, did not affect the feed consumption of broiler chickens. They showed that increasing dietary SP from 0 to 1 %, caused to increase in weight gain during total period. Shanmugapriya et al., (2015) reported that feeding 1% of spirulina platensis to broiler chicks caused to improve growth performance.The mechanism of action of Spirulina has not been clearly established, but previous studies have reported that dietary supplementation of Spirulina has positive effects on growth performance in poultry. Carcass yield and breast relative weight in chickens fed more than 0.5 % SP were significantly increased (P<0.05), but abdominal fat, liver and thigh relative weight were not affected. Similar to our results, increase in carcass percentage and ready-to-cook yields of broiler chicks were reported in the studies of Raju et al. (2004), Kaoud (2012) and Holman & Malau-Aduli (2013). In present study, the chickens fed more than 0.5% SP had lower cecal E.Coli concentration and nonsignificant increase in Lactobacillus concentration. Similarly, Park et al., (2018) indicated that broiler chickens fed a Spirulina supplemented diet led to higher cecal Lactobacillus concentration. Regard to previous study which concluded that intestinal microbial-including cecum is highly associated with the production performance of broiler chickens (Jeong and Kim, 2014), therefore in our study, the better performance of chickens fed higher than 0.5% SP may be associated with decrease in cecal E.Coli Concentration.Conclusion It is concluded that dietary supplementation of broiler diets with 1% Spirulina platensis, could improve the growth performance, carcass yield and cecal microbial population of broiler chickens at 42 day of age.Keywords: Prebiotic, Feed Conversion ratio, Carcass yield, Escherichia coli, Algae

This study aims to investigate the nutritional effects of organic acids, prebiotics, probiotics and (prebiotic + probiotic( combination on increasing adult bee population, neonatal rearing, beeswax production, pollen storage and hives weight gain before the honey harvesting season in Iranian honey bees.

This experiment was conducted using 25 Iranian honey bee colonies with the same sister queen and with the same conditions in a completely randomized design with 5 experimental treatments including control group (sugar syrup 1: 1), organic acid (8 cc per 1 liter of syrup 1:1), prebiotics (10 g per 1 liter of syrup 1: 1), probiotics (5 g per 1 liter of syrup 1: 1) and (prebiotic + probiotic) combination (10 g + 5 g per 1 liter of syrup 1: 1) and 5 repetitions for 30 days before the honey harvesting season.

The adult bee population in the colonies that received organic acid and prebiotic + probiotic( combination was significantly higher than the control treatment (p<0.05). Neonatal rearing and beeswax production increased in colonies that received organic acid, prebiotic, probiotic and )prebiotic + probiotic( combination compared to the control treatment (p<0.05). The effect of experimental treatments on pollen storage was not significant (p<0.05). Hives weight gain increased in all experimental treatments, except for the colonies that received probiotics, compared to the control treatment (p<0.05).

The results showed that the use of organic acid, prebiotic, probiotic and (prebiotic + probiotic) combination in bee stimulation feeding before the honey harvesting season can improve the performance of Iranian bee colonies.

Fermented Saccharomyces cerevisiae are used as a new additive in animals (Heidarieh et al., 2013). These products contain nucleic acids, chitin, beta-glucan and mannoligosaccharides. Researchers reported that feeding by Saccharomyces cerevisiae improves, improves growth performance in broilers (Baurhoo et al., 2006). Consumption of fermented Saccharomyces cerevisiae in rainbow trout, increased feed uptake and improved feed conversion ratio (Heidarieh et al., 2013). Due to the aforementioned effects of fermented Saccharomyces cerevisiae and insufficient reports on its use in broilers, the aim of this study was to investigate its effect on growth performance and immune responses.

An experiment was conducted as a completely randomized design using 240 day-old chicks (mixed sex) with four treatments, five replicates, and 12 chicks in each replicate from 1 to 42 days of age. Experimental treatments were included: (1) control group (basal diet without any feed additive), (2) basal diet+ 0.1 percent fermented Saccharomyces cerevisiae (3) basal diet + 0.3 percent fermented Saccharomyces cerevisiae and (4) basal diet + 0.5 percent fermented Saccharomyces cerevisiae.Chicks in each replicate were weighed weekly and feed intake was determined at the end of each week. From these data, average daily weight gain, average daily feed intake and feed conversion ratio were calculated. On day 42 of experiment, two birds (one male and one female) from each replicate were selected, weighed, then slaughtered and carcass yield and carcass components including breast, thighs, wings, abdominal fat, thymus and bursa of Fabricius were weighed using a digital scale and their relative weights to body weight were calculated.In order to assess the systemic antibody response, chicks were immunized by intramuscular injection of 0.1 mL of 25 % sheep red blood cell (SRBC) in PBS on days 8 and 22. Blood samples were collected from two birds of each replicate via the wing vein and serum antibody levels produced in response to SRBC were measured on days 21, 28, 35 and 42 (Salehimanesh et al., 2015). Skin response to intradermal injection of Phytohemagglutinin-P (PHA-P) was measured on day 16 during 24 and 48 h after injection (Grasman, 2010). Data were analyzed using the GLM procedure of SAS (SAS Institute, 2001) in a completely randomized design and means were compared using Tukey’s multiple range test at P<0.05.

The results indicated that treatments had no significant effect on daily feed intake (P>0.05) but daily weight gain and feed conversion ratio improved in all groups receiving fermented Saccharomyces cerevisiae (P<0.05). The beneficial effects of Saccharomyces boulardii and Bacillus cereus (Gil et al., 2005) and prebiotic (Fermacto) (Rodrigues et al., 2005) on broiler performance have been identified. It was reported that the use of probiotics (Primalac and Bacillus amyloliquefaciens) did not effect on daily feed intake (Yakhkeshi et al., 2012). In contrast, the use of lactobacillus reduced the daily feed intake of broilers (Murry et al., 2006). The difference can be due to the type and dose of the probiotic. By examining the effects of Saccharomyces cerevisiae and Bacillus subtilis on broiler performance, it was found that the probiotics increase growth performance, feed intake, and feed conversion ratio (Chen et al., 2009). It was reported that the use of 1.5 and 2% Saccharomyces cerevisiae (Sc47) in the diet of broiler chickens increased daily weight gain (Ghasemi et al., 2006). It was reported that addition of probiotic (containing Bacillus subtilis) in broiler chickens, improved the feed conversion ratio from 21 to 42 days of age (Fritts and Waldroup, 2003). In a study performed on broiler chickens fed mannanoligosaccharide (isolated from the cell wall of Saccharomyces cerevisiae), it was found that the feed conversion ratio was significantly reduced compared to chickens fed a mixture of probiotics and organic acids (Derebasi and Demir, 2004). Saccharomyces cerevisiae improves feed intake by stimulating beneficial microbes in the digestive tract (Kocher et al., 2004).The results indicated that treatments did not affected on carcass efficiency, breast, thigh and wing (P<0.05). All amounts of fermented Saccharomyces cerevisiae increased bursa of Fabricius and thymus weight ratio (P<0.05). Consumption of 0.1 and 0.3% fermented Saccharomyces cerevisiae reduced abdominal fat weight ratio (P<0.05). Feeding broilers with three diets, including probiotics of Primalac, Saccharomyces cerevisiae, and Aspergillus oryzae under heat stress, indicated that the weight of carcasses decreased, which could be due to their lack of effect under stress condition (Yaghoobfar et al., 2009). Researches indicated that consumption of lactobacillus reduces abdominal fat in broilers (Kalavathy et al., 2003). A study on the effect of probiotic (Lactobacillus) and synbiotic (Biomin) indicated that the spleen and thymus weight in the chicks consumed probiotic increased at 35 days compared to the group consumed synbiotic , but the weight of the bursa of Fabricius was not changed. According to the results of this study probiotics can affect the organs of the immune system, but their effect can vary, depending on the bacterial strain and the age of the bird (Awad et al., 2009). Non-significant changes for total anti-SRBC, IgG and IgM were observed on day 21 (P>0.05). Administration of 0.3% fermented Saccharomyces cerevisiae increased the total anti-SRBC and IgM on day 28 (P<0.05). Treatments increased total anti-SRBC, 0.3 and 0.5% fermented Saccharomyces cerevisiae increased IgG and 0.1 and 0.3%, increased IgM on day 35 (P<0.05). Total anti-SRBC was increased by 0.3 and 0.5% fermented Saccharomyces cerevisiae and IgG was increased by 0.5% on day 42 (P<0.05). Researchers reported that addition of prebiotics, probiotics or a mixture of these two additives increases the titers of immunoglobulins, which may indicate favorable effects of these additives on immunity of chickens (Ebrahimi et al., 2014). Kabir et al. (2004) reported that the use of Protexin had a positive effect on the immune response of poultry to the SRBC antigen. They generally suggest that the improvement of the immune system under the influence of probiotics is accomplished by increasing general antibodies, increasing macrophage activity, and increasing the production of local antibodies at the mucosal surface of tissues such as the intestinal wall. It was reported that the use of synbiotic Biomin (Hasanpour et al., 2013) and synbiotic Protexin + TechnoMos (Ghahri et al., 2013) increased humoral immune responses. In contrast, it was reported that the use of probiotic BioPlus, prebiotic Biomass and their composition had no effect on serum IgG concentration in broiler chickens (Midilli et al., 2008), the differences between the researchers' findings could be related to the probiotic, prebiotic and synbiotic dose used, the animal species and population studied (age and weight) and microorganism strains. Cellular immunity in response to PHA-p injection was not affected by treatment groups (P>0.05). Diets containing lactobacillus have been shown to improve T lymphocyte function in newly hatched chickens and pullets (Dunham et al., 1993). It was reported that probiotic (Protexin) improved cellular immune function, as well as concomitant use of probiotic and formic acid did not have a synergistic effect on poultry cellular immune system (Mirbabai et al., 2012).

It was concluded that consumption of 0.3% fermented Saccharomyces cerevisiae in broiler diets improved growth performance and humoral immune response.

Antibiotics have been widely used in animal production for decades to promote growth. Although there is a trend toward reducing antibiotics in diets and now in Europe new laws have been passed to ban their use. As a result, economically important diseases such as enteritis necrosis (NE), which is caused by Clostridium perfringens in chickens, have become more prevalent. The alternatives to antibiotic growth promoters could affect gut health and performance by their impact on intestinal microflora. The purpose of this experiment was to compare the efficacy of some feed additives as alternatives to antibiotic for preventing of subclinical necrotic enteritis in broilers.

The study was conducted using 336 one-day-old male broiler chicks in a completely randomized design with 7 treatments, 4 replicates and 12 chicks per replicate. The treatments included: 1) Negative control (NC, corn-soybean meal-based diet without any feed additive); 2) Positive control (PC, diet containing wheat and fish-meal without any feed additive); 3) Antibiotic (PC diet + zinc-bacitracin); 4) Probiotic (PC diet + probiotic); 5) Prebiotic (PC diet + prebiotic); 6) Phytobiotic (PC diet + phytobiotic); and 7) Organic acid (PC diet + organic acids).

The results indicated that addition of antibiotic or its alternatives to the PC diet did not affect average daily feed intake, average daily gain, feed conversion ratio and relative weight of internal organs (p>0.05). Evaluation of cecal bacterial population at d 41 showed that chickens were infected by subclinical necrotic enteritis. The count of Clostridium perfringens was significantly lower in broilers fed either phytobiotic or antibiotic than in broilers recieved either NC or PC treatments. Broilers fed probiotics, prebiotics or organic acid in their diet had lower counts of Clostridium perfringens in cecal contents than those fed PC diet (p<0.05), however the difference was not significant when compared to NC treatment (p>0.05).

According to the sampling results on days 29 and 41, addition of phytobiotic compared to antibiotic, increased the number of lactobacilli while reduced the count of Clostridium perfringens and coliforms. Therefore, phytobiotic can be a suitable alternative for antibiotic to promote gastrointestinal health and prevent subclinical necrotic enteritis in broilers.

An experiment was conducted to evaluate the effects of ASRI1, ASRI2, commercial growth promoter and prebiotic on performance, carcass characteristics and small intestinal morphology of broiler chickens. A total number of 875 day-old Ross 308 chickens were used in a completely randomized designed as a 2×3 factorial with six treatments, five replicates of 25 birds per each. Chickens were fed with three types of growth promoter (ASRI1, ASRI2 and commercial growth promoter) and two levels of prebiotic (0 and 1 kg/ton of diet). Body weight, feed intake and feed conversion ratio were not affected by herbal growth promoter and prebiotic (p>0.05). Effects of growth promoters and prebiotics on carcass characteristics were not significates, but prebiotic reduced the carcass yield (p < 0.05). Relative weights and lengths of intestinal tracts and morphological indices were not affected by growth promoter and prebiotic. Finally, based on the results of this research, commercial growth promoters could be substituted by ASRI1 and ASRI2.

This experiment was conducted to investigate the effects of supplementation of different levels of peribiotic of mannan oligosaccharide (MOS) (Celmanax) on performance and some blood parameters of broiler chicks under induced ascites. 320 day-old Ross 308 male chicks were randomly divided into 4 treatments with 4 replicates. The dietary treatments included: positive control (corn – soybean meal basal diet), negative control (induced ascites with sodium chloride supplementation in the drinking water), negative control with supplementation of (2 and 4 ml per liter of drinking water of mannan oligosaccharide. Feed intake, Body weight and feed conversion ratio were measured at the end of the experimental period (42 d). Dead birds were dissected for ascites symptoms. Blood and ascites parameters (Right ventricular weight to total ventricles ratio (RV/TV) were also measured at 42 days of age. The statistical analysis of the data was done by using SAS software and comparison of the means were done by Tukey test at a significant level of 5%. The results showed MOS increased weight gain and decreased feed conversion ratio in birds with ascites (P <0.05). Both MOS levels significantly decreased the hemoglobin, red blood cells count, protein and hematocrit content of  birds reared under induced ascites (P <0.05). In addition, supplementation of 4cc/l  MOS on drinking water significantly decreased mortality rate caused by ascites (3.3%) and RV/TV index (P <0.05). In Conclusion, the supplementation of 4 cc MOS per liter of drinking water can improve growth performance of broiler chickens and can reduce the mortality rate of chickens reard unedr induced ascites.

This study investigated the effects of different levels of prebiotic and peptide supplementations on growth performance, apparent digestibility of nutrients and fecal score in suckling Zell lambs. A completely randomized experiment was designed with a factorial arrangement of 3×2 containing 36 male suckling Zell lambs at the age of 10 days and with a mean weight of 4.4±0.33 kg for 70 days. The treatments consisted of 1- control (without prebiotic and peptide), 2-0 g of prebiotic and 2 g of peptide, 3-1.5 g of prebiotic and 0 g of peptide, 4-1.5 g of prebiotic and 2 g of peptide, 5-3 g of prebiotic and 0 of peptide, and 6-3 g of prebiotic and 2 g of peptide per day for the experimental lambs in milk replacement. The results of mean feed intake and daily weight gain of experimental lambs showed a significant difference between experimental treatments (P< 0.05), so were higher in  treatment of 2 g peptide and 1.5 g prebiotic. There was a significant difference in the apparent digestibility nutrients in DM, OM, CP and ADF peptide and peri-biotic interaction effects (P<0.05). In results of fecal score, there was a significant decrease in consistency score of 1.5 g prebiotics (P<0.05). Carcass traits significantly improved by treatment of 2 g peptide and 1.5 g prebiotic. There was no significant difference in the results of feed conversion rario (FCR) and body dimensions. The overall results showed, feed intake significantly increased by treatment of 2 g peptide and 1.5 g of prebiotic and improved daily gain and fecal score in some experimental periods as well as carcass traits in lambs.

In order to compare the effect of prebiotic and various types of fibers on performance and some physiological parameters of broiler chickens, an experiment was performed with 320 chicks with eight treatments in a completely randomized design. Dietary treatments were basal diet (corn-soybean meal), basal diet with prebiotic (Biolex, MB40), and various sources of fiber (wheat bran (WB), soybean hull (SH), and palm kernel meal (PKM)). Different types of fiber and prebiotics were added to the diet at 1.5,3% and 2 g/kg, respectively. The birds that consumed 1.5% of PKM had the best feed conversion ratio compared to the other treatments except 3% of PKM and control diet (P<0.05). Abdominal fat pad significantly decreased in birds that consumed various types of fiber compared to the control diet (P<0.05). Apparent ileal digestibility of organic matter and crude protein increased in birds that consumed 3% palm kernel meal (P<0.05). The apparent ileal digestibility of ether extract decreased in birds that consumed PKM compared to the control diet (P<0.05). Dietary inclusion of various types of fiber caused a significant decrease in plasma cholesterol and triglycerides compared to the control diet (P<0.05). The results showed that dietary inclusion of PKM improved performance, decreased abdominal fat pad and E.coli and coliform population of cecum and increased digestability of crude protein and population of Lactobacillus of cecum in broiler chickens.

The purpose of this study was to compare effects of the different types of feed additives consumption including probiotics, prebiotics and synbiotics in Japanese quails. A total of 384 Japanese quail chicks were randomly assigned to 8 treatments with 4 replicates and 12 birds per replicate (cage). The experimental diets (treatments) were included: Basal diet without additive (control) and protexin 0.2 g/kg (probiotic), Yeast 2 g/kg (probiotic), Fermacto 1.6 g/kg (prebiotic), Tepax 1 g/kg (prebiotic), Biomin IMBO 1 g/kg (synbiotic), Protexin 0.1+Fermacto 0.8 g/kg (synbiotic), Yeast 1+Tepax 0.5 g/kg (synbiotic) which were added to the basal diet. feed intake and body weight was higher (P<0.05) in quail fed detail containing additives.. The best feed conversion ratio were observed in quails fed diets containing tepax, yeast, biomin IMBO and fermacto (P<0.05). The use of additives affected the blood glucose, albumin, globulin and immunoglobulins A and G levels (P<0.05). In the laying birds at the early stage of laying, the amount of blood triglycerides increased with diets containing synbiotic additives (P<0.01) The LDL level increased in females fed additive with exception of tepax and yeast+tepax (P<0.01). In male quails fed with the diet containing of the additives, the concentration of immunoglobulin M increased and HDL level decreased (P<0.05). The use of synbiotics and prebiotics improved the growth performance and increased blood albumin to globulin (A/G) ratio as an index of osmotic pressure in the blood. It is possible to use feed additives particular synbiotics while maintaining and improving the health of quails for organic meat and eggs production without the use of vaccines and antibiotics.

Japanese quail is considered as a beneficial bird because of its characteristics such as rapid growth, early maturity, high egg production, breeding times and short incubation period (Lotfipour and Shakeri, 2011). Additives such as probiotics and prebiotics are used as alternatives to antibiotic growth promoters today (Zare Shahneh et al. 2007). Primalac is a kind of commercial probiotics that contains Lactobacillus casei, Lactobacillus acidophilus, Bifidobacterium thermophilum, and Enterococcus faecium (Salehimanesh et al. 2016). Its characteristics include increasing the population of the gastrointestinal tract microbes, increasing livestock production, reducing drug use, reducing mortality and reducing diarrhea in the flock (Midilli et al. 2008). Fermacto (kind of commercial prebiotics) is the product of elemental fermentation of Aspergillus oryzae. Fermacto have effects of increasing the flock's uniformity, reducing the passage of foodstuffs, eliminating the competitive challenge, developing intestinal villi, increasing energy and protein absorption, increasing the absorption and storage of minerals especially calcium and phosphorus, enhancing the immune system, and improving weight gain on time of stress (Ghahri et al. 2013). An experiment was conducted as a completely randomized design using 400 day-old quail chicks (mixed sex) with four treatments, five replicates, and 20 quail chicks in each replicate from 1 to 42 days of age. Experimental treatments were included: (1) control group (basal diet without any feed additive), (2) basal diet contains 0.9 g/kg Primalac, (3) basal diet contains 2 g/kg Fermacto and (4) basal diet contains 0.9 g/kg Primalac + 2 g/kg Fermacto. Diets were formulated to meet or exceed the nutritional requirements of Japanese quail as indicated in the standard tables (NRC, 1994). Quails in each replicate were weighed weekly and feed intake was determined at the end of each week. From these data, average daily weight gain, average daily feed intake and feed conversion ratio were calculated. On day 42 of experiment, two birds (one male and one female) from each replicate were selected, then weighed, were slaughtered and carcass yield and carcass components including breast, thighs, wings, abdominal fat, fat around neck, and bursa of Fabricius were weighed using a digital scale and their relative weight to body weight were calculated. The length of the various parts of the small intestine, including the duodenum, jejunum and ileum, was measured after the separation from the mesenteric with the ruler. To study the blood metabolites, blood samples were taken from the wing vein of two quails in each replicate (one male and one female) on day 42 and then, sera were separated to measure triglycerides, cholesterol, HDL, and LDL using enzymatic kits via colorimetric method. To determine ileal microbial population of quails, after opening the abdominal cavity, ileum region, between Meckel’s diverticulum and ileocecal junction, separated by a sterilized scissor, about two centimeters of the ileum were transferred into sterile microtubes and were stored at -20 ̊C until studying E.coli, lactobacillus and coliform microbial populations (Roostaei-Ali Mehr et al. 2014). Eosin methylene blue agar medium (Merck, Germany) was used to culture E.coli. MacConkey agar (Merck,
Germany) and MRS (Merck, Germany) were used to cultivate coliforms and Lactobacillus, respectively. The results indicated that 0.9 g/kg probiotic Primalac, 2 g/kg prebiotic Fermacto, and 0.9 g/kg probiotic Primalac + 2 g/kg prebiotic Fermacto in diet had no significant effect on daily feed intake, daily weight gain, and feed conversion ratio (P>0.05). It was reported that the use of probiotic (Primalac) to the diet of Japanese quail had no effect on daily weight gain and daily feed intake (Rezaeipour et al. 2015). Several factors can affect the consumption of bird feed, including the physiological and nutritional factors, health and the rate of production and type of bird (Blair, 2008). The results indicated that treatments did not affected on weight of carcass and internal organs (P>0.05; Table 3). It was reported that using probiotic to the diet of Japanese quail had no effect on weight of carcass and carcass traits (Sahin et al. 2011). It was reported that addition of probiotic (Primalac) and prebiotic (Fermacto) to the diet of broilers did not have any effect on growth performance and carcass quality, carcass weight, carcass traits, breast, heart, abdominal fat, spleen, and bursa of Fabricius (Shirmohammad et al. 2015). Treatments had no significant effect on relative length of the small intestine segments (duodenum, jejunum and ileum) (P>0.05). Shirmohammad et al. (2015) reported that intestinal traits of broilers were not affected by Primalac and Fermacto. Since the most important feature of probiotics is their ability to settle in the gastrointestinal tract, native microbial strains of gastrointestinal tract are usually prepared as probiotics, so probiotics produced for broilers may not be suitable for establishment or proliferation in the Japanese quail digestive system. Treatments had no significant effect on triglyceride, cholesterol, HDL, and LDL (P>0.05). It is reported that the supplementation of the Japanese quail diet with Primalac did not have any effect on serum triglycerides, cholesterol, LDL, and HDL of broilers (Rezaeipour et al. 2015). Sahin et al. (2008) reported that cholesterol, triglyceride and glucose levels were not affected by experimental treatments when using synbiotic (Saccharomyces cerevisiae + mannan oligosaccharide) in Japanese quail diets. The levels of serum cholesterol and triglycerides in birds affected by diet and other factors such as age, sex, and environmental conditions (Haddadin et al. 1996). Non-significant changes for intestinal microflora were observed (P>0.05; Table 6). Researchers reported that the consumption of probiotic (Protexin) in the diet of quail did not have any significant effect on bacterial populations (Nasehi et al. 2015). When using feed additives, consideration of points such as rate of consumption, temperature, humidity, water consumption and environmental health are necessary (Chiang and Hsieh, 1995). It could be concluded that 0.9 g/kg probiotic (Primalac), 2 g/kg prebiotic (Fermecto) and synbiotic (0.9 g/kg probiotic Primalac + 2 g/kg prebiotic Fermecto) had not any positive effect on growth performance, carcass traits, length of small intestine, serum lipids as well as the number of Lactobacillus bacteria, coliforms, and E.coli in Japanese quail.

The aim of this experiment was to determine the effects of different microbial products on the performance and health of Baluchi lambs. 40 Baluchi make lamb with mean age of one year and initial body weight of 30 kg ± 1.5 kg for 90 days were used in a completely randomized design with four treatments and ten replicates. Experimental diets were 1) basal diet (control group), 2) basal diet +0.5 gr probiotic, 3) basal diet+2 gr of prebiotic 4) basal diet+0.5 gr probiotic +2 gr of prebiotic per head (sheep) per day. Body weight (BW) and body growth measures were recorded First and period End. Feces were scored weekly. The pH ruminal fluid was determined immediately after sampling and straightening it. The results of this experiment showed that mean BW was higher in probiotic than other groups (52.85). There was no difference between treatments for the final weight, daily gain, feed intake and feed conversion rate. Also, there were no significant differences between treatments in health indicators, fecal consistency and digestibility of nutrients. The results of this study indicated that with use probiotic, pH ruminal fluid was increased and there was a significant difference between the control group (P <0.05). Overall Results of this experiment indicated that supplementation probiotics did not have a significant effect on the performance and health indicators of pre-growing lambs.

This study was carried out toinvestigate the effect ofmannan-oligosaccharide prebioticonperformance,egg quality, immune response, intestine ileum microflora and nutrient digestibility in laying hens fed various levels of crude protein. A total of 150 Hy-Line W-36 layinghens were assigned to a 2×3 factorial arrangement of treatments. Experimental diets consisted of 3 levels of crude protein (recommended level for strain, 90 and 95% of recommended level) and 2 levels of mannan-oligosaccharides (0 and 0.1% of diet). Reduction of crude protein to 10% of basal diet resulted in decrease of egg weight, egg production, egg mass and feed conversion ratio (P